The SAGE Graphics Architecture

Abstract

The Scalable, Advanced Graphics Environment (SAGE) is a new high-end, multi-chip rendering architecture. Each single SAGE board can render in excess of 80 million fully lit, textured, antialiased triangles per second. SAGE brings high quality antialiasing filters to video rate hardware for the first time. To achieve this, the concept of a frame buffer is replaced by a fully double-buffered sample buffer of between 1 and 16 non-uniformly placed samples per final output pixel. The video output raster of samples is subject to convolution by a 55 programmable reconstruction and bandpass filter that replaces the traditional RAMDAC. The reconstruction filter processes up to 400 samples per output pixel, and supports any radially symmetric filter, including those with negative lobes (full Mitchell-Netravali filter). Each SAGE board comprises four parallel rendering sub-units, and supports up to two video output channels. Multiple SAGE systems can be tiled together to support even higher fill rates, resolutions, and performance.